Nowadays, display devices are increasingly being used in people's work, learning and entertainment. Generally, when a user uses a display device in different scenarios, intensities of ambient light around the display device in different scenarios are different. In order to adjust brightness of a display screen of the display device, it is often required to install an ambient light sensor in the display device, obtain brightness information of the ambient light by the ambient light sensor, provide the brightness information to a processing module of the display device, and adjust the brightness of the display screen of the display device by the processing module according to the obtained brightness information of the ambient light.
However, since the ambient light sensor must be installed in the display device and the display device needs to supply working electric energy to the ambient light sensor, an overall power consumption of the display device is larger.